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v Systems and their structure, their individual dynamics, their interactions, their adaptation to changing conditions, and their evolution shape this world... The success of individuals, collectives, and human society is directly related to the quality of their systems knowledge enabling them to utilize the opportunities offered by their system environment.
v Some systems behave in a simple, easily predictable way. Others respond in a complex process to inputs from their environment, sometimes with considerable delay. Others adapt their behavior to different challenges and may even change their structure and behavioral characteristics in an evolutionary process.
v This book is a guide to the more complete understanding of systems. The modeling of systems is an essential tool for understanding systems: In most cases, systems are too complex or inaccessible for direct and full inspection, and understanding must come from models approximating the real system's structure and behavior... Obviously, the question of model validity poses itself as a major issue in the analysis of real systems.
p.3 Much of the study of dynamic systems is therefore concerned with defining and building mathematical or computer models and studying their dynamic behavior... Knowledge gained from the study of models can be used to understand and perhaps manage and control the real system (provided we have a valid model!).
p.4 As the level of system complexity increases, new basic system needs appear... Each of these basic needs will have to be satisfied to a minimum degree for the system to be viable. These basic needs categories will therefore "orient" the behavior of more complex systems; we call them "basic orientors". Most of the basic orientors appear as response to fundamental properties of the system environment, but some are entirely the consequence of specific system qualities.
p.5 Systems are therefore characterized by elements and an essential influence structure between them, which allows the fulfillment of certain functions defining system purpose and system identity. In systems analysis and modeling, the principal task will be to find the essential elements and their functions and to establish the essential influence structure of the system.
p.8 system structure defines behavior
p.15 Models and simulations have always been an essential part of the human experience: Before arriving at a decision, we use mental models to determine possible outcomes, and evaluate their potential costs and benefits... the computer can track the multitude of implications of complex relationships and their dynamic consequences much more reliably than the human mind... The basic modeling approach is identical for all disciplines... This is because the properties and behavior of dynamic systems are determined not by their physical structure and appearance but by their system structure and processes.
p.16 systems analysis, modeling, and simulation therefore also assist in gaining a much more general understanding of dynamic systems and their behavior and of the world around us.
p.20-21 If the model describes the behaviorally relevant structure correctly, it is "structurally valid". Since the behavior of the system follows from a correct representation of structure, the model can also be expected to be "behaviorally valid"... Because they explain behavior as a function of structural relationships, structural models can be employed to simulate responses to conditions that have not been observed before, to investigate the whole range of possible behaviors and development paths, and to study and understand conditions and possibilities for system change.
p.28 All system models are sketches or "caricatures" of the real system. The model purpose determines the simplifications and aggregations used. The model purpose has to be clearly defined to reflect the task to be solved... The expected influences from the system environment must be determined, and their points of influence on the system structure must be specified... structural (explanatory) modeling concentrates on the definition and recognition of the behaviorally relevant system structure. In this process, the system analyst works closely with experts, scientists, and actual actors in, or operators of, the system in order to develop a model of the relevant system structure.... the initial model concept is a verbal model.
From this verbal model the influence relationships are extracted and combined in the influence structure, usually also in graphical form as an influence diagram... In this phase of the work, the emphasis is on revealing the system structure.
p.30 the computation of future paths requires "scenarios"... These scenarios should be plausible, consistent, and complete... The spectrum of possible future... influences on the system should be covered by a complete set of scenarios.
p.31 For large and complex systems, systematic evaluation is necessary to compare alternative development paths. Mapping of indicators of system state on quality criteria is required also when choosing among policies to manage a system.
p.36 Constraints limit the possible states of a system.
p.36 most systems... have components that cannot react immediately, called state variables, states, stocks, or levels. A state can only be changed at a certain rate, and it may take some time before a significant effect on the state can be noticed.
p.39 System behavior cannot be deduced from the properties of system components alone; the system is more than the sum of its parts. System behavior is therefore an emergent feature of the system, i.e. of its particular configuration of system elements and their interconnections.
Systems therefore cannot be understood by studying their parts; they can only be understood by analyzing them as wholes. This points to the essential role of system structure. It defines how elements of a system are connected and influence each other, often in feedback loops.
More than anything else, system structure is responsible for the characteristic behavior of a system. This fact, by the way, is not usually recognized by traditional science.
p.44 Nonlinear dynamic systems are what the world is all about and why it is sometimes so difficult to understand.
p.46 Systems modeling for anticipative monitoring of future paths and timely feed-forward control obviously also makes a lot of sense
p.49 Self-organization denotes the ability of a system to change its system structure and its functions to cope with new challenges
p.62 System models are usually greatly simplified representations of the real system.
p.63 Self-organization is the essential process of system change in the systems of the real world. It has its own characteristic dynamics that must be understood if it is to be used for effective control of system development.
p.63 Successful orientation of behavior for the purpose of viability in a given environment requires respecting properties of the specific environment and the possibilities and limitations of the system.
p.64 Identification of the system structure - in particular its feedback structure - is fundamental to the analysis; the influence graph is the essential first step... Dynamic systems from the simple to the very complex determine literally everything that happens in the world... Mathematical systems analysis is a common language for understanding systems and generalizing research results
p.65 Recognition of the behaviorally relevant system structure and its representation in the influence diagram constitute the first phase of model development. The influence diagram permits some qualitative conclusions about the system it represents, but these results are neither sufficient nor reliable for understanding exactly how a system may behave over time.
p.66 The influence diagram captures the behaviorally relevant structure of the system. It is therefore the basis for any simulation model. Because of its importance for the success of model development, the influence diagram has to be developed with care and precision.
p.67 In developing the influence diagram, one is often tempted to simultaneously consider other concurrent influences. Not only is this unnecessary, it also leads to errors and is therefore not permissible. Each single influence must be analyzed under ceteris paribus conditions ("the other (influences) remain the same"). Viewing each influence in isolation without having to consider other simultaneous influences makes the modeling task much easier. The correct mutual interplay of all influences is found later as a result of the relationships and feedback links of the influence diagram. One must strictly focus on one relationship at a time and resist the temptation to consider simultaneously all influences which could play a role. It is the task of the simulation model to determine the net result of simultaneous influences from other components of the system.
p.68 To capture their dynamics correctly, real systems cannot usually be represented by linear approximations, and more accurate representations of system components and their functional dependencies have to be used. Modeling of dynamic systems requires a close look at the individual elements and their particular role and function in the system. Introducing their specifications into the influence diagram, we obtain the simulation diagram which - together with information about the elements and the characteristics of their interconnections - contains all the information necessary to program and compute the simulation.
p.154 There are two kinds of concepts that orient decisions and behavior of human actors: (1) factual knowledge (correct or incorrect) about the world, and (2) normative orientations ("orientors": goals, values, social norms etc.). In nonroutine decision-making, i.e. considered choice, the two kinds of concepts are processed and linked in complex information processing.
p.158 The set of criteria that are relevant for the evaluation of system development will be referred to as orientors. This term is used to make clear that we are dealing with criteria that systems (or their managers) use to orient their decisions and actions regarding the system. Orientors are aspects, terms or dimensions (like "freedom") that designate important criteria or qualities of system survival and development but not the degree to which they must be satisfied.
To evaluate system development with respect to the relevant orientors, indicators describing the system state must be mapped on the orientors in order to compare the actual system state with the corresponding goal values in "orientation space".
In the evaluation of system development, three different types of normative criteria play a role: 1. Constraints... 2. Quality measures... 3. Weights
p.159 Path analysis of a simulation model, i.e. the study and comparative evaluation of alternate development paths, represents one important task of system analysis. It is possible to develop an overview of behavior by many probing simulation runs but a systematic approach is always preferred. Orientation theory... offers a framework for systematic and efficient path studies.
p.160 The first task of path analysis consists of quickly finding the most relevant development paths despite a multitude of uncertain, time-dependent, or adjustable parameters. The efficiency of this search depends on how cleverly possible parameter constellations are combined in consistent and plausible "scenarios."
The second task of path analysis is the comparative evaluation and assessment of different development paths to clarify which path (or which group of paths) should be preferred. In this phase of the work, evaluation criteria have to be introduced that reflect the existence and development interests of the system (and perhaps also the interests of its managers)... 1. We must make sure that the necessary minimum level of orientor fulfillment is achieved for each individual orientor. 2. We must determine the total quality of orientor satisfaction (for individual orientors and some aggregated quality measure). In comparing different paths of system development, the most favorable path will be the one for which (1) the minimum conditions are always satisfied for all orientors, and (2) the overall orientor satisfaction is better... We denote as a "scenario" a set of internally consistent and plausible assumptions concerning the future development of exogenous quantities.
p.162 As natural systems evolve, their environment forces them to respect its fundamental properties, leading to the emergence of "basic orientors" - criteria that have to be respected by the system in its behavior... This assures that only systems... with a viable, robust, and adaptive system structure survive.
p.170 An understanding of nonroutine behavior is possible only if the relevant "orientors of nonroutine behavior" are known and understood. Orientors are meaningful to a system only if the state of the system itself, and that of the environment relevant to the system (i.e. the "system and environmental state") can be assessed with respect to the orientors. This requires first that the system perceive the system and environmental state through a set of indicators... It requires second that the perceived system and environmental state can be mapped on the relevant orientor space.
p.174 It is trivial but important to note that meaningful nonroutine behavior (including a trial-and-error approach) can only occur by reference to what has been called "orientors": standards, norms, goals, objectives, values, basic needs, etc. The possible successes of unoriented nonroutine behavior can be nothing more but chance successes. Orientors are thus key elements of nonroutine behavior... In routine behavior orientors are not needed, as available response programs are applied without concern for their consequences.
p.175 Orientation of nonroutine behavior. Conditions in the system and environment are perceived via a set of indicators. The perceived indicator state is mapped on the relevant orientor space. The resulting (dis)satisfaction vector guides the choice of control policy. Before application to the real system, likely results of the chosen control policy are projected using the internal model. The projected state changes are again mapped on orientor space to produce a new (dis)satisfaction vector which serves to correct the control policy originally chosen. When the projected dissatisfaction is acceptable, the control policy is applied in the real system.
p.179 For our purposes the supreme orientor is much too general to be of much use. We are interested in the next level of orientors ("basic orientors") which follow from the confrontation of the supreme orientor with the basic operational capabilities and limitations of the system and the essential characteristics of the environment. Thus the set of basic orientors derives from the question: "Given the global features of the system and of its environment, what basic orienting dimensions must the system refer to in its nonroutine behavior, and in particular in fundamental behavioral decisions in order to fulfill the global instruction of the supreme orientor?"
p.180 It is impossible to understand, let alone predict, the vagaries of nonroutine system response without a knowledge of the upper level orientors, and in particular the basic orientors. It is for this reason that we focus our attention on the basic orientors: They are the key to understanding system behavior.
p.182 Orientation theory [JLJ - footnote: Bossel 1977c, Orientors of nonroutine behavior, Concepts and Tools of Computer-assisted Policy Analysis] argues that there are "basic orientors" just "below" the ultimate goal (of viability) that represent "fundamental interests" and are common to all self-organizing systems, irrespective of their physical nature, because they have developed in response to certain "fundamental properties" that are common to all system environments.
p.182-183 Adequate fulfillment of each of the basic orientors is required for survival, viability, and success. The essential idea is that in coevolving with their environment, successful systems evolve structures and functions that allow dealing successfully with the particular features of the environment. This appears to an observer as if the system's behavior is (consciously) directed by the "basic orientors" as normative constraints. Conversely... if actions are directed by explicit reference to the "basic orientors", they can be expected to lead to viable and successful behavior and development.
A system can "perceive" the static and dynamic features of its environment only in terms of the physical flows (material, energy) and information flows it receives from the environment.
p.183 Systems must be compatible with their system environment and its characteristic properties in order to be viable and to exist sustainably.
p.185 Corresponding to the six fundamental environmental properties, there are therefore six environment-determined basic orientors (EXISTENCE, EFFECTIVENESS, FREEDOM OF ACTION, SECURITY, ADAPTABILITY, COEXISTENCE) that apply to all autonomous self-organizing systems.
p.186 The set of basic orientors can therefore be used to represent the fundamental viability interests of a system in a way in which the set of primary colors (red, blue, yellow) can be used to reproduce any picture in "full color". As each basic orientor stands for a unique requirement, a minimum of attention must be paid to each of them. Compensation of deficits of one orientor by over-fulfillment of other basic orientors is therefore not possible.
p.189 Orientation theory postulates that systems evolving in a given environment can only survive if they learn to cope with the fundamental environmental properties, i.e. if they pay a necessary minimum of attention to each basic orientor.
p.205 A system state is perceived through the observation of (exact or fuzzy) indicators... Of particular importance are the orientors just below the supreme orientor, i.e. the basic orientors... If a given system is to be viable in its system environment, this imposes certain requirements on its "design". These requirements (or "system interests") are denoted as "basic orientors". They are system counterparts of the fundamental properties of the environment
p.206 The basic orientors are each unique, i.e. independent of each other and are not mutually substitutable. They are complete in the sense that they cover all aspects imposed by the fundamental properties of the environment.
p.206 The invariance of basic orientors together with the nonlinear feature of orientor switching provides the system with the ability to cope flexibly and adaptively with a widely and quickly changing state of system and environment.
p.207 The assessment of system development requires the observation of indicators, i.e. certain system variables for which goal values must be defined.
p.207 The selection of the indicators must be complete, i.e. it must be able to provide a comprehensive picture of the instantaneous system and environmental state, as far as they are relevant to the system.
p.207 As long as constraints are not met, attention has to focus on these gaps. Compensation of a deficit by overfulfillment of other constraints is not permissible. This is particularly true for the basic orientors.
p.207 The attention rank of indicators is established from a consideration of their satisfaction rating, the weights of orientors on which each indicator loads, and from the state-dependent loading of each indicator on the orientors.
p.208 Scenarios are plausible assumptions concerning the bundle of future exogenous influences that may determine the development of a system.
p.209 In more complex processes, a better understanding of systems and their reliable representation in models can mean the difference between success and failure
p.209 In searching for principles to guide sustainable development, it is only natural to have a closer look at the global ecosystem, which has demonstrated sustainability over a few billion years.
p.218 Contributions from the very different scientific disciplines... are all relevant to... sustainable development in particular... What is primarily needed is not more specialist research in each of these fields, but integration of concepts and knowledge which are already available. This requires a major paradigm change in the way science and society view and organize themselves
p.234-235 To successfully cope with unforeseen developments, the human system must allow for structural dynamics and structural diversity. Structural dynamics means allowing for permanent change and development, including creative destruction and reorganization of structure, and dynamics change of active memory... Structural diversity... increases the creative and innovative potential of the human system - as in ecosystems. Increasing diversity in any evolving system improves the chances for successfully coping with future challenges. Diversity... protects from ruinous competition for the same resources... and... reduces stress in the system.
p.236 Diversity enhances system adaptability in ecosystems as well as in social systems by enlarging the pool from which innovative responses to new challenges can be drawn
p.236 As in ecosystems, balanced attention to, and satisfaction of, the basic system orientors (existence needs, effectiveness, freedom of action, security, adaptability, and coexistence needs) will facilitate the path towards sustainability of human systems. It will allow the best possible response to changing conditions, without a teleological prescription of system development.
p.238 To sustain something implies valuing it enough to put an effort into maintaining its integrity.
p.243 Balanced satisfaction of basic orientors of present and future components of the global ecosystem and of the human system appears to be the foremost requirement for sustainability, i.e. adequate attention to existential needs, security, freedom, effectiveness, adaptability, coexistence needs. These basic orientors must be reflected in system goals, structure, and organization. Orientor-guided decision-making can substitute for the lack of evolutionary control of human action. It will lead to sustainable development without requiring specification of intermediate or end states.
p.244 If system behavior is guided by balanced reference to basic orientors it will have the best chance for success in the long run... Balanced basic orientor satisfaction of all systems and actors in a regional system is synonymous with sustainability. Systems which have evolved under evolutionary forces to be sustainable... can be viewed as having been designed in a way to achieve balanced satisfaction of basic orientors... To be efficient and effective, path analysis, policy synthesis, and system design for sustainable development have to take the orientor satisfaction of affected systems into account. Orientor impact assessments can be used to compare the impacts of various development paths on ecosystems and social systems, to find sustainable solutions which are feasible and acceptable, and to identify those paths which cause the least disruption and provide best orientor satisfaction to the system and its subsystems... Orientor impact assessments put comparative evaluation of development paths and sustainable states on a sound systems-theoretical base.
p.245 Using orientor impact assessments, promising policies and strategies can be identified more quickly and reliably.
p.246 Sustainability of human systems must therefore be a dynamic concept... it amounts to allowing continual structural change in a system... The quest for sustainability must allow creative and adaptive evolution of human systems while maintaining essential values... and... diversity. The course of this evolution, i.e. its development path and resulting sustainable states therefore cannot be accurately predicted. Moreover, it cannot be planned except perhaps for the short term. It is therefore essential to introduce constraints and devise self-correcting controls which ensure a path of sustainable development without specifying the details... it will produce.
p.249 Diversity... provides the potential for coping with changing conditions by facilitating system change and self-organization. In evolution, a dynamic feedback process causes diversity to increase... Diversity also reduces competitive stresses... by avoiding identical resource requirements... Diversity therefore contributes to better satisfaction of all orientors.
p.252 We have now collected all the tools we need for constructing a system of indicators for assessing the viability of systems, and in particular progress in sustainable development. [JLJ - great. Now we can use these tools for related purposes, such as developing a strategy for a machine playing a game.]
p.256 Indicator selection... requires (subjective) choice... Except for simple cases, there is currently no method for objectively measuring indicator impact on orientor satisfaction. These impact functions therefore have to be generated by subjective assessments.
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